1. Field of the Invention
The present invention relates generally to a key cylinder arrangement for use with locks and the like type of devices. More specifically, this invention relates to a key cylinder arrangement for automotive application wherein a key cylinder is adapted to be inserted into a retention cavity from outside of a structure such as a vehicle door, ignition switch or the like, and which features a simple and robust construction.
2. Description of the Prior Art
Automotive door locks usually take the form of a cylinder type lock arrangement that consists of a key cylinder and a rotor rotatably supported within the cylinder. A key lever is typically connected to the rear or inboard end of the rotor, and a door lock device is operatively connected by way of a rod to the key lever. A cylinder type door lock is arranged such that the key lever is operable via the key cylinder only when a matching key is inserted.
There are problems with this type of known structure. In particular, since the key lever rotates together with the rotor of the key cylinder it is necessary to replace both the key cylinder and the key lever if the rod displacement changes with a change in vehicle door type, etc. For this reason, it has been difficult to use exactly the same parts under all conditions and this has led to a greater number of parts being required for a given number of different vehicle types and has contributed to higher production cost.
This problem has been exacerbated by the fact that this type of prior art door lock structure requires a rod holder, an additional part, to connect the key lever to the rod, and thus further increases the number of parts required.
A further problem has been encountered in that the key cylinder, or the handle assembly that contains it, normally is installed from the outside of the door panel with no automatic means of retention, thus necessitating a contemporaneous retention operation from inside the door panel, which, in turn requires installation of the key cylinder early in the overall assembly process of the vehicle, in particular, before the outer and inner door panels are fastened together and installed on the automobile, which, in turn, sometimes leads to an assembled automobile with mismatched key cylinders.
A further problem is that retention of the key cylinder is often so weak that application of a strong external force can overcome the structural strength of the retention means allowing the key cylinder to be "punched out" in a manner that allows unauthorized entry into the vehicle.
A further problem is that keys are sometimes lost in transit from the manufacturer to the dealer.